A common problem for owners of in-ground sprinkler systems, wherein the underlying piping is completely embedded in the ground with the sprinkler heads rising above ground level, is that grass grows excessively immediately around each of the lawn sprinkler heads. The excessive growth can occur to such a degree that it virtually covers the sprinkler heads and seriously interferes with their proper operation. An added problem of the excessive growth is that the sprinkler heads become hidden and thus are prone to be run over by a lawnmower and be damaged by the wheels or blades of the lawnmower.
Various prior art designs have attempted to overcome the above mentioned problems and such are exemplified in U.S. Pat. No. 2,751,250 to Block, U.S. Pat. No. 3,762,642 to Di Santo, and U.S. Pat. No. 5,211,338 to Leite et. al. The Block Patent discloses an earlier concept wherein a plate assembly is provided in a slight recess in the ground and has slots to enable installing two semi-circular plates around the sprinkler body and under the flange portion of the sprinkler head. U-shaped closure clips keep the installed plates together in place. The Block device is time consuming to install, requiring the soil around a sprinkler head to be dug away a sufficient distance to enable the plates to slide under the flange portion of the sprinkler head. In addition, using the closure clips to lock the plates together is a cumbersome operation.
The Di Santo patent discloses a grass guard comprising two member pieces of which the first piece has a slot in it enabling installation under the top flange of a sprinkler head. The second piece, a slot closer piece, having grooves in the edges is slideably received in the slot to close the ring and complete coverage of the space immediately under the flange. A tongue-in-groove relationship of the slotted piece and the slot closer piece facilitates the alignment. The Di Santo device suffers the disadvantages that the tongue and groove locking mechanism is relatively expensive to manufacture, and that the grooves can trap dirt, thus making the sliding motion difficult.
The Leite patent discloses a sprinkler shield of a single plate construction having a plurality of radial slots extending from a central bore to provide sufficient flexibility to allow the plate to be installed around an existing sprinkler head. Thus, installing the sprinkler shield requires bending the plate and pushing the sprinkler head through the radial slots which can have the undesirable consequence of inadvertently damaging either the sprinkler head, the sprinkler shield, or both.
It may be appreciated therefore that there is a need for a new and improved sprinkler guard which is easy to use, reliable, and can be manufactured at low cost.